The former `Frasier` star`s 28-year-old daughter Spencer Grammer gave birth to a baby boy on Monday (10.10.11).
It is the actress and her husband James Hesketh`s first child together and they have named their son Emmett Emmanual.
The tot weighed in at 7lbs 7 oz and Spencer`s representative has revealed both "mother and son are doing wonderfully".
Kelsey just missed the birth because his daughter went into labour just as he and his wife Kayte Walsh were jetting out to Australia.
The 56-year-old actor is heading Down Under to appear as the key speaker at the Australian Commercial Radio Awards, which take place on the Gold Coast this weekend, and although he is disappointed he couldn`t be there to see Emmett arrive he has received a photo of him.
Speaking on The Kyle and Jackie O Show on Australian station 2day FM, Kelsey joked: "My grandson`s birth began just before we took off - we also just welcomed a new niece into the family about a month ago, we keep timing it so people to into labour, and we disappear and we get pictures, we don`t have to deal with it until they`re a little more cleaned up and presentable."
Kelsey is looking forward to spending a few days in Australia with Kayte because he has never been to the country before.
He said: "I`ve never been - I love the idea of being in Australia, so I`m getting a sneak preview - I`m here for six days and I`ll have to come back - I came with my wife Kayte."